I would go with 2". It will settle down to 1-3/4" but it looks good and leaves a little rake for when or if you tow. I think if I would have went 2.5" it would have been nose high and I would have had to add a 1/2" or 1" spacer in the rear. Also it depends on the tire size you are going with. If you do 2.5" front and 1" rear a 33" tire might still look small. Just my opinion though.
See my photos above for 33's with a 2.5" kit.
Could they be bigger? Sure, but I don't think they look disproportionately small either.
As for the kit settling. In my experience none have settled to less than the designated height, but that may depend on brand and if you're using top hat or pre load spacers. This has been my experience based on 4 of the Rams I've had ('07, '12, '14 and '21) and 2 of my brother's F150's (not sure the years on those), all with top hat spacers of various brands.
I agree that 2.5" without a rear spacer will be nose high. That probably depending on the truck but mine had 2.25" of rake when it was at stock configuration, so no rear spacer would have left me 1/4" nose high.
With the 2.5/1.5 kit, I've got 1.25" of rake. If I had gotten the 1" set for the rear instead of the 1.5" set I would have 3/4" of rake now which is about perfect. Doing it all again, I'd do that. Actually, since I have the lifetime alignment, I'm considering swapping the rear spacers but that'll probably be a project for spring since I don't like working on cold trucks.